Butterfly valve arrangement for a combustion engine having external ignition

ABSTRACT

For a combustion engine having combustion spaces therein, an ignition circuit for delivering an ignition spark to the combustion spaces, a butterfly valve for controlling the fuel mixture to said combustion spaces, a closure spring for returning the butterfly valve into a closed position when the associated accelerator is not actuated, the ignition circuit including the closure spring as an element, whereby when the closure spring develops a discontinuity, the ignition circuit is prevented from delivering a spark to the combustion spaces.

United vStates Patent 11 1 Scholz I BUTTERFLY VALVE ARRANGEMENT FOR A COMBUSTION ENGINE HAVING EXTERNAL IGNITION lnventor: Norbert Scholz, Wolfsburg,

Germany [73] Assignee: Volkswagenwerk Aktiengesellschaft,

Wolfsburg, Germany Filed: July 16, 1973 Appl. No.: 379,352

[30] Foreign Application Priority Data Aug. 31, 1972 Germany 2242737 U.S. Cl. 123/198 DC, 123/142, 123/148 S, 123/198 D Int. Cl. F02b 77/08, F02p ll/OO Field of Search.. 123/198. D, 198 DA, 198 DC, 123/198 DB, 118, 142, 148 S References Cited UNITED STATES PATENTS 2/1964 Frederick 123/198 DC X [451 Feb. 4, 1975 3,273,552 9/1966 Plath 123/198 DC 3,487,183 12/1969 Scholmanmn 123/198 DC X Primary Examine rCharles J. Myhre Assistant Examiner-Tony Argenb right Attorney, Agent, or Firm-Ernest F. Marmorek 2 Claims, 2 Drawing Figures BUTTERFLY VALVE ARRANGEMENT FOR A COMBUSTION ENGINE HAVING EXTERNAL IGNITION FIELD OF THE INVENTION The present invention relates to a butterfly valve arrangement for a combustion engine having external auto-ignition, especially those which are used in motor vehicles and, which have a locking spring or closing spring associated with the butterfly valve.

BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide in a combustion engine an improved butterfly valve arrangement of the above described type in which, in the event the locking spring associated butterfly valve will break or otherwise becomes inoperative, the locking spring will not cause an undesired acceleration of the vehicle by affecting the butterfly valve in the above manner.

Accordingly, the present invention provides that the locking spring associated with the butterfly valve in a combustion engine is made part of the ignition circuit by being a current-conducting element thereof.

As a result, and due to the fact that the locking spring of the butterfly valve is made an electrical component of the ignition circuit arrangement, the ignition circuit, in the event the locking spring breaks or is disabled due to other conditions, will interrupt the circuit and thereby will cause a stalling of the motor.

In a preferred embodiment of the present invention, the locking spring constitutes an element placed in a connecting line between the ignition coil and the breaking contact. Itis noted that the locking spring and its bearings, as well as its surroundings, are provided with appropriate insulations so that the otherwise proper electrical operation of the vehicle is assured. In the event, for example, the locking spring is mounted on a lug of the carburetor, on the gas distributor of the combustion engine, and on a pivoting lever which is coupled with the butterfly valve, then such a lug must be made from an insulating material or at least must contain an insulating material on its surface. It is also preferred that the locking spring itselfor its immediate surrounding is shielded with an insulating material so that in the event the locking spring breaks, the portion of the spring which comes in contact with the hot terminal of the power supply, will not cause a short circuit of the entire automotive circuit. The question and de tails of insulation should be understood by an average expert in the field of the automotive electrical art.

In the event the locking spring breaks when the vehicle, for example, is in the middle of a very busy intersection or, when the vehicle is in the middle ofa critical BRIEF DESCRIPTION OF THE DRAWING The invention will become more readily apparent from the following description of preferred embodiments thereof shown, by way of example, in the accompanying drawing, in which:

FIGS. 1 and 2 are schematic illustrations of the parts of the combustion engine which are necessary for the understanding of the operation of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1 it is noted that the combustion engine is provided with a carburetor 1 which, in the event of a combustion engine having fuel injection, should identify the fuel distributor. Into the carburetor 1, in the lower portion thereof with respect to the flow direction of the gas mixture, a butterfly valve 2 is mounted on a shaft 3 which, in turn, is fixedly coupled with a lever 4, with the help of which the butterfly valve 2 can be rotated within the carburetor l in a wellknown manner. The pivoting movement is caused by a rod 5 which, in turn, is coupled with the accelerator 6 of the vehicle.

One of the arms of the lever 4 is coupled with a locking spring 7 which at its other end portion 8, as seen in the figure, is secured to the carburetor body 1. The locking spring 7 is preferably formed as a tension spring and, 'as a result of which, when the accelerator 6 is not operated, the butterfly valve 2 will pivot into its closed position by undergoing a counterclockwise rotation, as viewed in the figure. The figure schematically illustrates only certain portions of the combustion engine which are necessary to understand the operation of the present invention, and it shows the ignition arrangement which includes a battery 9, an ignition switch 10, an'ignition coil 11, an ignition condenser 12 and a breaker contact 13, all connected into the circuit as shown. Of course, the delivery of the ignition spark to the spark-plug is illustrated only schematically by the arrow. The ignition coil 14 is connected to the breaker contact 13 by means of a conductor 14.

According to the present invention, the locking spring or closure spring 7 is connected into the conductor 14 between the ignition coil 11 and the breaker contact 13 as an electrical element itself, so that when the closure spring 7 breaks, or a discontinuity affects its mechanical activity, the ignition current circuit becomes interrupted and, as a result, the combustion engine will be turned off. One will understand, consequently, that when the accelerator 6 is not actuated or operated, the vehicle will not undergo an acceleration even when the closure spring 7 is broken and the butterfly valve 2 cannot pivoted into its closing position.

As has already been explained. under the broad concepts of the present invention and shown in FIG. 2, as

3 an alternative, the closure spring 7 is made a part of the electrical excitation circuit 15 of a relay 16 which is energized through the ignition contact 10 and which relay has an operating contact 17 placed into the connecting conductor 14. In this case, when the ignition contact 10 is closed, the ignition current passes over the normally closed contact 17 when the closure spring 7 is in normal condition. On the other hand, when the closure spring 7 breaks, the excitation circuit of the relay 16 will be opened, whereupon the normally closed contact 17 of the relay will open the circuit passing through the conductor 14, which is the ignition circuit.

The above mentioned relay, according to the presentinvention, is designed to include a delayed feature, that is, its contact 17 will open only with a certain delay after the closure spring 7 has broken and will interrupt the ignition circuit only with such delay.

The butterfly valve 2, under the broad concept of the present invention, should also includean air quantity regulating device which is used in the air suction system ofa combustion engine having fuel injection. it is noted that in all the above described structural arrangements the preventive circuit arrangement, according to the present invention, will operate quickly and prevent damage to the engine which otherwise would flow from the very high revolutions which would be present, such as, for example, during the coupling of the engine and, solely caused by the broken closure spring 7 and the consequently resulting opened position of the butterfly valve 2.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

Having thus described the invention, what I claim as new and desire to be secured by Letters Patent, is as follows:

1. In a combustion engine having combustion space means, an ignition arrangement for deliverying an ignition spark to the combustion space means, a butterfly valve means for controlling the fuel mixture to said combustion space means, a closure spring means for returning said butterfly valve means into a closed position when an associated accelerator is not actuated, said ignition circuit arrangement including said closure spring means, whereby when said closure spring means develop a discontinuity, said ignition circuit arrangement is prevented from delivering a spark to said combustion space means wherein said ignition circuit arrangement includes an ignition coil means and an interrupter contact means, a circuit portion connecting said ignition coil means with said interrupter contact means, said closure spring means being placed into said circuit portion.

2. In a combustion engine having a combustion space means, an ignition arrangement for delivering an ignition spark to the combustion space means, a butterfly valve means for controlling the fuel mixture to said combustion space means, a closure spring means for returning said butterfly valve means into a closed position when an associated accelerator is not actuated, said ignition circuit arrangement including said closure spring means, whereby when said closure spring means develop a discontinuity said ignition circuit arrangement is prevented from delivering a spark to said combustion space means wherein said closure spring means are connected into an energizing circuit of a delayed action relay means, an operating contact of said relay means being placed into said ignition circuit arrangement. 

1. In a combustion engine having combustion space means, an ignition arrangement for deliverying an ignition spark to the combustion space means, a butterfly valve means for controlling the fuel mixture to said combustion space means, a closure spring means for returning said butterfly valve means into a closed position when an associated accelerator is not actuated, said ignition circuit arrangement including said closure spring means, whereby when said closure spring means develop a discontinuity, said ignition circuit arrangement is prevented from delivering a spark to said combustion space means wherein said ignition circuit arrangement includes an ignition coil means and an interrupter contact means, a circuit portion connecting said ignition coil means with said interrupter contact means, said closure spring means being placed into said circuit portion.
 2. In a combustion engine having a combustion space means, an ignition arrangement for delivering an ignition spark to the combustion space means, a butterfly valve means for controlling the fuel mixture to said combustion space means, a closure spring means for returning said butterfly valve means into a closed position when an associated accelerator is not actuated, said ignition circuit arrangement including said closure spring means, whereby when said closure spring means develop a discontinuity said ignition circuit arrangement is prevented from delivering a spark to said combustion space means wherein said closure spring means are connected into an energizing circuit of a delayed action relay means, an operating contact of said relay means being placed into said ignition circuit arrangement. 